Vacuum cleaner



FIG. 1 is a right side perspective view of a vacuum cleaner, showing my new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a front view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a right side view thereof. 

The ornamental design for a vacuum cleaner, as shown and described. 